many points (time domain) will my output signal have?
The tuning word specifies the output frequency as a fraction of the reference
clk frequency, therefore a tuning word representing fout =1Mhz, with a system
clk of 10Mhz, will be represented digitally as 1/10.
The phase accumulator is actually a modulus M counter that increments its
stored number each time it receives a clock pulse, therefore when you generate
a 1Mhz o/p using s system clk of 10Mhz, you will have 10 o/p sample points in
your o/p signal.